<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>固定定位</title>
    <style>
        .one, .two {
            width: 200px;
            height: 200px;
        }

        .one {
            background-color: red;
            position: fixed;
        }

        .two {
            background-color: green;
            width: 400px;
        }
    </style>
</head>
<body>
<div class="one"></div>
<div class="two"></div>
</body>
</html>
